The terms software defined radio (“SDR”) and software radio (“SR”) apply broadly to the technique of using software to define and implement portions of a radio system that would previously have been implemented using custom-built hardware. The power of general-purpose processors and software configurable hardware has steadily risen to a level where they can perform many of the computationally intensive digital signal processing (“DSP”) functions performed by radio systems and SDR capitalizes on this increase in power. The SDR software component is typically a hardware device (e.g., a field programmable gate array) which has been configured by software, or a program executing on a general-purpose computer. This SDR software component typically interfaces, via data communication channels, to an SDR hardware component providing the functionality necessary to support SDR tasks that cannot be accomplished by the reconfigurable hardware module or general-purpose computer being used (e.g., the analog transmission and reception of radio signals and analog filtering of the received analog signals).
In modem SDR systems, the SDR hardware component typically provides little of the total SDR functionality as most of the DSP work can presently be done using software. SDR allows the functionality defined by software to be redefined without requiring the replacement of hardware components. Instead, only the software that defines these functional modules is replaced. The more functionality that is defined by software, the more flexible and reconfigurable the resulting SDR becomes. The combination of the SDR hardware component and SDR software component can be used to support a variety of radio standards by running a different SDR software component for each implementing standard.
As a result of the complexity and various nuances of the great many radio standards that exist, the SDR software components implementing these radio standards may be provided by an equally large variety of third party providers. Despite their relative simplicity, a great number and variety of SDR hardware components with varying capabilities are also available. Each SDR software component must be equipped to interface with an SDR hardware component as well as with client applications which make use of the SDR to send or receive data. Supporting each of the methods for a client application to connect to the SDR software component, and the many available SDR hardware components quickly becomes a daunting task for those providing the SDR software components, distracting them from their core area of concern and competency. Furthermore, a majority of the effort necessary to provide such support is repeated by each of the providers of SDR software components. These factors currently limit the universality and practicality of SDR systems.